The conveying of objects frequently involves the problem that the objects must be transferred from a first conveying means to a second conveying means in order to change, e.g., the velocity or the position of the objects in relation to one another or both.
A drum-like device for transferring cans or tubes to be processed from a conveying means arriving at the device to a conveying means exiting from the device at another velocity has been known from DE 40 10 601 C1 for the automated manufacture of cans or tubes. The prior-art transfer device has a rotatingly driven rotor, to which a plurality of holding means for conveying the objects to be transferred are articulated. The articulation of the holding means is performed by means of a pivoted lever with guide rollers, which is rotatably mounted on the rotor and rotates around the rotor a-is during the rotation of the rotor and is restrictedly guided in the process along a cam arranged stationarily in relation to the machine. The holding means are fastened to the circumferential-side ends of rigid pivoting arms, which are mounted rotatably on the rotor axis, are coupled with the control means of the holding means via multilink transmissions to generate a nonuniform angular or rotation velocity of the holding means, and thus they rotate around the rotor axis. To securely hold the objects during the conveying through the transfer device, they are suctioned by the holding means.
A device for cutting and feeding cigarette filters has been known from U.S. Pat. No. 3,010,561. Multiple-length cigarette filters are delivered here by a dispenser onto a wheel equipped with cups on its circumference. The multiple-length cigarette filters are subsequently cut into three filter pieces of equal length. The filter-receiving cups arranged on the rotatable wheel are mutually adjustable in the circumferential direction and in the axial direction of the axis of rotation of the wheel, so that the individual receiving cups aligned next to one another can be adjusted and aligned one behind the other. Pivoted levers and cam rollers with cam plates that are in functional connection are used for adjusting the receiving cups in the circumferential direction. During the adjustment of the receiving cups around the axis of rotation of the wheel, the receiving cups mutually have nonuniform velocities depending on the design of the cam plates.
U.S. Pat. No. 3,286,809 pertains to a cutting and mixing-sorting device especially for cigarette filters. The device has a feed unit, from which the multiple-length cigarette filters are transferred to a conveying drum. The conveying drum is in functional connection with a cutting means, with which the multiple-length cigarette filters are cut into parts of equal length. Furthermore, the conveying drum is divided into one middle disk and two outer disks, wherein the middle disk has half-round recesses for receiving the middle part of the filter. The two outer drum disks are in functional connection with mutually and independently adjustable pivoted levers, which have semiround recesses for receiving the outer parts of the filter. Each multiple-length filter piece is cut on the receiving drum with a cutting means into a middle filter piece and two outer filter pieces. The cut filter parts, located next to one another, are delivered into a row one behind the other by means of pivoted levers, which are arranged movably on both sides of the receiving drum, in connection with the rotatable receiving drum, and they are at the same time displaced from the two outer drum disks onto the middle drum disk. The pivoted levers, designed as toggle levers, are controlled by cam plates or cams as a function of the rotation of the drum. To hold the individual filter bodies, holding shields are provided in the circumferential direction of the drum disks in the area of the filter-receiving cups, or vacuum can be admitted to the filter-receiving cups.
The primary object of the present invention is to design an inexpensive device with a rotor with at least one holding device supporting an object via a vacuum for conveyance from a conveying device running to the rotor to a conveying device running from the rotor such that a simple, compact device will be obtained.
According to the invention, a device for transferring objects is provided, especially hollow bodies, such as cans, tubes and the like, from an arriving conveying means to an exiting conveying means. The device includes at least one, rotatingly driven rotor, at least one holding means for the said objects, which is articulated to the said rotor for common drive, and at least one control means connected to the holding means, which control means is restrictedly guided along a cam to generate a nonuniform conveying velocity of the holding means. The holding means is mounted on the rotor pivotably around a pivot axis located at a spaced location from a rotor axis.
The present invention is based on a device for transferring objects from an arriving conveying means to an exiting conveying means, which has a rotatingly driven rotor, at least one holding means articulated to the rotor for common drive for conveying the objects from the arriving to the exiting conveying means, and a control means, which is connected to the holding means and is restrictedly guided to generate a nonuniform velocity of the holding means during the conveying of the objects to be transferred on the basis of a cam and carries the holding means with it in the process.
According to the present invention, the holding means is mounted at the rotor pivotably around a pivot axis, which does not coincide with the rotor axis but is located at a spaced location therefrom. As a result, the pivoting movement around the pivot axis located at a spaced location from the rotor axis, which pivoting movement is controlled by the control means, is superimposed to the rotary movement around the rotor axis. The holding means must be only accelerated or decelerated relative to the rotor corresponding to the velocity ratios in the transfer section. The number of transmission links between the control means and the holding means can be considerably reduced. While a multiarmed multilink transmission and additionally a pivoted lever are required according to the state of the art, the transfer device according to the present invention needs only one two-armed one-link transmission per holding means, and the rotor itself is a transmission link of the two-armed transmission.
A second transmission link, which is rigid in itself, is preferably mounted at the rotor pivotably around a pivot axis that is preferably parallel to the rotor axis. The second transmission link is preferably designed as a two-armed pivoted lever. A first arm of the pivoted lever, which is used as a support for the holding means, points in a radial direction to the rotor axis. A roller is preferably arranged as a control means at the second arm projecting from the holding means over the pivot axis. The control means is pressed by means of a restricted guiding means, preferably a compression-spring, against a machine-side cam, which is designed such that the desired velocity profile is achieved for the holding means.
Besides the simplification of the transmission mechanism, the device according to the present invention has the inherent advantage that the holding means can be connected to a vacuum source or can be supplied with a pressurized medium in a very simple manner. This is advantageous in the case of applications in which the objects to be transferred are held at or in the holding means by suction, supporting the reliable conveyance in the transfer section. In the opposite case, this also applies to applications which require a pressurized medium for support.
A fluid-tight connection of the holding means leads according to the present invention through its drag bearing. An especially simple and therefore preferred fluid connection is obtained if the holding means is arranged on a shaft around the pivot axis, which has an opening on one of its front sides, through which opening the holding means can be connected to a vacuum or pressure source. The fluid connection is thus performed according to the present invention via a single interface, at which two parts movable in relation to one another abut against one another. The two superimposed movements of the holding means, namely, the rotary movement of the first transmission link, of the rotor, and the pivoting movement of the second transmission link, the pivoted lever, are integrated according to the present invention in a single connection interface.
The rotor and a plate cam located opposite the rotor on the front side cooperate according to the present invention for the fluid connection in the manner of two distributing plate cams. In a partial area of its surface which is swept by the drag bearing or the shaft of the holding means, the plate cam arranged on the machine side has a recess, via which the holding means is connected to the vacuum source or the pressure source. The pivoting movement of the pivot shaft does not need to be taken into account here, in particular. In contrast, each holding means must be connected to a vacuiu source via two rotary connections according to the state of the art in order for the holding means to be able to perform a suction function, because the rotor must first be connected, and the holding means, which performs a relative movement in relation to the rotor, must then be connected from the rotor.
In a preferred embodiment, a device according to the present invention is used to transfer objects which are introduced by the arriving conveying means one after another and are removed by the exiting conveying means next to each other. In a preferred application, namely, in the manufacture of hollow bodies, especially tubes and cans, such a conveying problem arises, e.g., when the hollow bodies are to be dried in a drying or baking device, or a lacquer layer previously applied is to be baked in. The conveying velocity through the drier or through the oven is low in this case of application compared with the velocity at which the objects arrive because of the necessary exposure time. In order not to disturb the continuity of the entire manufacturing process, the hollow bodies introduced one after another are conveyed through the drier or the oven in groups located next to each other. The conveying velocity through the drier or the oven is reduced corresponding to the number of regrouped hollow bodies, i.e., in proportion to the hollow bodies introduced one behind the other to the hollow bodies forwarded next to each other.
The conveying means are usually horizontal conveyors, especially conveyor belts with conveying shells, in which the objects are located individually. However, the present invention is not limited to this. The transfer device is preferably formed by a so-called transfer drum.
A preferred exemplary embodiment of the present invention will be described below on the basis of figures.
The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which a preferred embodiment of the invention is illustrated.